i. Technical Field
The present invention relates to baseplates for tools. More specifically, the present invention relates to a novel baseplate for routers, edging machines, milling machines, saws and polishing tools. These tools are commonly used to work and finish many different types of materials including masonry, stone, glass, ceramic and metal. Routers, edging machines and milling a machines are commonly used, for example, to carve a particular edge design in a counter top or sheet of glass. Saws are commonly used to cut many different types of materials including masonry, stone, glass, ceramic and metal. Polishing tools are used to finish and polish many different types of materials including masonry, stone, glass, ceramic and metal. The baseplate of such tools is generally described as the portion of the tool that contacts the substrate upon which work is being done, excluding the blade or wheel of the tool.
ii. Background Art
Routers, edging machines, milling machines, saws and polishing tools have been known in the art for a considerable time. Generally, such tools are quite heavy (for example, approximately sixty pounds) and are difficult to move across the surface of a substrate.
In prior art masonry tools, for example, one approach taken to minimize this problem is to place ball casters in the baseplate of the tool. For example, until recently, at least one manufacturer of masonry routers used nylon balls positioned in the baseplate. These balls are designed to roll across the surface of the substrate easing movement of the router. One disadvantage of this approach is that fragments of the substrate and dust are impressed into the ball and/or caught in the ball socket. These fragments or dust may then jam the ball and prevent the ball from rolling smoothly. This makes the tool difficult to move and control. The fragments and dust may also become caught between the ball and the substrate surface. In such a situation, movement of the tool may result in the surface of the substrate being scratched. This is especially disadvantageous when working with a substrate which has a surface that is finished and polished.
One approach the prior art has taken to minimize the problems associated with the ball casters described above is to eliminate the ball casters and produce a cushion of water under the baseplate. Pursuant to this approach, water is expelled from the baseplate and the baseplate of the tool floats across the substrate surface on the cushion of water without the use of ball casters. While this approach avoids the jamming and scratching problems described above, it does not always result in easy movement across the substrate surface. This problem is particularly pronounced when the tool approaches a corner of the substrate. In such a situation, the cushion of water deteriorates as the water runs over the edge of the substrate and the tool no longer floats across the substrate surface. Rather, the tool must be dragged along with its baseplate resting directly on the substrate. This presents scratching problems and results in the tool being difficult to move and control. The difficulty of movement and control is particularly problematic when it occurs at a corner which often requires more attention to detail than a straight edge.
U.S. Pat. No. 5,784,789 (“Vargas”) discloses a rotary trim saw for cutting materials in difficult to reach places. Vargas teaches that the trim saw may have a base having ball caster type wheels.
German Patent Document No. DE 3,404,555 (The “German Disclosure”) discloses an apparatus for machining a stack of metal sheets. The German Disclosure teaches that the stack of metal sheets may be held against each other and against the work table surface by hydrostatic pressure. The machine blade is surrounded by a ring, with multiple nozzles. Pressurized fluid is pumped from the nozzles such that there is a clearance between the underside of the ring and the top metal sheet. The German Disclosure teaches that by holding the sheets in position in this manner, the top sheet is not damaged in the machining process.
None of the foregoing prior art have suggested the present invention.